PROBLEM TO BE SOLVED: To provide an oxygen-absorbing pre-filled syringe which has excellent oxygen barrier properties and preferably excellent water vapor barrier performance, keeps strength through long-term storage and substantially suppresses formation of low-molecular compounds after oxygen absorption.SOLUTION: An oxygen-absorbing pre-filled syringe stores an agent in a sealed state and is configured so as to be capable of releasing the sealed state in use to pour the agent. The pre-filled syringe comprises, in order, a first resin layer containing at least a thermoplastic resin (b), an oxygen-absorbing layer containing an oxygen-absorbing composition and a second resin layer containing at least a thermoplastic resin. The oxygen-absorbing composition comprises at least one compound having a tetralin ring of a specified structure, a transition metal catalyst and a thermoplastic resin (a).
